A dog’s coat is one of its most identifiable physical characteristics. Whether it’s scruffy or silky, long or short, almost every dog is covered in hair — and so are most owner’s homes. While we don’t need to be professional groomers to be familiar with a canine’s follicles, most people tend to use the terms “hair” and “fur” interchangeably when referring to their dog. But should they?
Dr. Cherie Pucheu-Haston, an associate professor of veterinary dermatology and immunology at the Louisiana State University School of Veterinary Medicine, says an appropriate way to consider the subtle differences between dog hair and fur is based on the number of strands that come from a single follicle opening.
“People will use the term ‘hair’ for animals that have ‘simple’ hair follicles, which means only one hair exits per hair follicle opening. This includes humans, horses, and many cattle,” she says. “In contrast, the term ‘fur’ is often used in animals that have ‘compound’ hair follicles, in which multiple hairs emerge from the same hair follicle opening. This includes dogs and cats.”
Dogs have multiple layers of hair, which as a whole is considered fur, says Dr. Lara Sypniewski, clinical associate professor and chair of the Henthorne Clinical Professorship of Small Animal Medicine at Oklahoma State University.
“Dogs have primary, secondary and tertiary hair. Humans only have tertiary hair, therefore we do not have fur,” she says. “Essentially, they are the same, dogs just have more layers.”
Fur can look and feel wildly different within the canine family. Pucheu-Haston says it’s unknown why fur grows differently between breeds, but that three phases of fur growth can help explain the looks and grooming requirements of certain dogs. Anagen is the “active growth” phase of fur growth, she says, while the “resting” phase is called telogen and the phase in between both stages is called catagen.
Most dogs will spend different amounts of time in each phase. Poodles spend most of their lives in the anagen growth phase, Pucheu-Haston says. This can explain why they tend to shed less, and what little fur these dogs do shed can sometimes get caught up in the constantly growing follicles, requiring regular grooming.
Longer-haired breeds, including Samoyeds and Chow Chows, spend most of their time in the telogen phase, Pucheu-Haston says, which is defined by a lack of new growth rather than shedding. They will eventually shed much of their fur, but they might spend months or longer in this period, which is why we often see them with such long coats.
Though a dog’s coat might vary by breed, there’s nothing about its fur that speaks to its allergenic or hypoallergenic qualities.
“Knowing humans are often allergic to dog proteins found in saliva and dander, a hypoallergenic hair coat is simply impossible,” says Dr. Michael Lorenz, a retired professor and dean of veterinary medicine at Oklahoma State University. “Owners can potentially reduce dander and shedding through good grooming practices, including routine brushing and bathing.”
Maintaining the dog’s fur is critical to his or her overall health, as well. After all, Sypniewski says, “the skin is the largest organ in the body, and the hair coat is a representation of skin health.”
Here are three conditions that affect the coat that owners should be on the lookout for:
One of the most common problems — and one that can impact any dog with medium to long coats — is matting. While it might not sound like anything more than a cosmetic problem, it can be painful for dogs and can lead to more serious problems if untreated.
“Mats can be somewhat uncomfortable, as the wadded-up hair can pull when the animal
is moving. In bad cases, mats can interfere with the animal’s ability to move,” Pucheu-Haston says. “In addition, the dense matted hair traps moisture, dirt, debris, and parasites and holds them all close to the skin. In some cases, maggot infestations can develop under the mats.”
Dogs with coats that are susceptible to matting should be checked frequently for matting. This can be done visually, but the best method is simply running your hands through the dog’s coat. Any areas where your fingers can’t slip cleanly through the fur and touch the skin should be inspected more carefully for the development of tangles or mats, which can feel like cotton balls caught up in the fur, Pucheu-Haston says.
The most common areas where mats are found on a dog’s body include around the anus, under the tail, over the hips, and on the belly. Frequent brushing and bathing are the best ways to prevent matting altogether.
Sypniewski says seasonal allergies, or atopy, can cause intense itching and make the skin susceptible to bacterial and yeast conditions.
Additionally, allergic reactions to foods may manifest themselves on the skin through itchiness, loss of fur, or scabs or hot spots (where dogs lick excessively due to allergy-related discomfort). A diet that’s anchored by a high-quality protein source and fatty acids should go a long way toward keeping your dog’s coat and skin healthy, Sypniewski says, but if you notice any signs of allergic reactions after changing foods or introducing new ones, you should make note of this and discuss it with your vet in a timely fashion.
While maintaining a clean healthy coat won’t prevent these, it’s nonetheless important that you monitor a dog’s coat and skin closely in order to identify growths that may be cancerous so that you can have them examined by a vet in a timely fashion, Sypniewski says.
“When owners groom their pets often they are able to recognize the presence of any growth on or below the skin,” she adds. “Although most canine skin tumors are benign, it is essential that a veterinarian evaluate the lesion and confirm that it is a benign growth. Malignant skin tumors do occur and are best managed when they are small.”